package com.briup.reggie.controller;

import com.briup.reggie.common.R;


import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * 文件的上传和下载
 * 图片
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件，需要转存到指定位置，否则本次请求结束时临时文件就会被删除
        log.info(file.toString());

        //获取原始文件名
        String originalFilename = file.getOriginalFilename();
        //获取原始文件名后缀(aaa.jsp,获取jsp这个后缀）
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID重新生成文件名，防止名字重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix;

        //创建一个目录文件
        File dir = new File(basePath);
        //判断目录是否存在
        if (!dir.exists()){
            dir.mkdir();
        }

        try {
            file.transferTo(new File(basePath + fileName));
        }catch (IOException e){
            e.printStackTrace();
        }

        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //输入流，通过输入流从文件读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath+name));
            //输出流，通过输出流写回浏览器，展示给用户
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("/image/jpeg");
            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
